Subsurface electric current generating apparatus



July 12, 1960 R. c. BAKER EI'AL SUBSURFACE ELECTRIC CURRENT GENERATING APPARATUS Filed Jan. 30, 1956 1/0IIIIIIIIIIIIIIIIIIIIIlI/IIl/Iiiifi 3 Sheets-Shae 1 July 12, 1960 SUBSURFACE ELECTRIC CURRENT GENERATING APPARATUS Filed Jan. 30, 1956 a1? -83 ea 8.62 we 6' 52 6' 47 1 was ii $.54 4-- R. c. BAKER L 2,944,603

s Sh eets-Shee't 2 July 12, 1960 R. C. BAKER ETA!- SUBSURFACE ELECTRIC CURRENT GENERATING APPARATUS Filed Jan. 30, 1956 3 Sheets-Sheet 3 77/0/Wi5 M 19/964 (674 0V M/[A/TS BY 7711, 669; M We SUBSURFACE ELECTRIC CURRENT APPARATUS Reuben C. Baker, Coalinga, Thomas M. Ragan, Downey, and Cecil W. 'Wents, South Gate, Calif., assiguors to.

Baker Oil Tools, Inc., Los Angeles, Calif., a corporation of California s 7 Filed Jan. '30, 1956, Ser. No. 562,237 19 Claims. (Cl. recs The present invention relates to well apparatus, and

more particularly to subsurface apparatus useful in the performance of different operations inoil, gas, water,

and similar well bores.

A further object of theinvention is to provide a subsurface electric current generating apparatus adapted to be lowered in a well bore on-a running-in string, in which institution of electric current generation is responsive to manipulation of the running-in string, and

in which operation of the apparatus can be prevented by suitable manipulation of the running-in string.

1 An additional object of the invention is to provide an improved spring motor device for rapidly rotating an electric generator disposed in a well bore. Yet another object of the invention is tofiprovide an improved'spring motor adapted to be disposed in a well bore' for rotating other equipment in the well bore, the spring motor being stu'rdily, built I and comparatively simple'in construction and operation, while being capable of storing and transmitting a large amount of energy.

Still a further object of 'the invention i's;to provide a spring motor having'an improved releasable l'atch'mechanism for preventing operation of the'motor untildesired.

Another object of the invention is to provide a' spring motor apparatus adapted to be lowered ina well bore on a running-in string, operation of the apparatus being instituted in response'to manipulation of the run- M ning-in string. More specifically, the apparatus includes a friction drag device adapted to frictionally engage the 2,944,603 Patented July 12, i960 Thisinvention possesses many other-advantages, and has other'objects which may be made more clearly apparent from a consideration of a form in which it may be embodied. 'This form is shown in the drawings accompanying and forming part of the present specification; It will now be described in detail, for the purpose of illustrating'thej general principles of the invention; but it is to be'understood that such detailed description is not'to be taken in a limiting sense, since the scope of the invention is bat defined by the appended claims. Referring to the drawings: Figure 1 is a side elevational View on a reduced Scale,

of apparatus embodying the invention and adapted tov be lowered in a well bore;

Figs. 2, 2a and 2b together constiute a side elevational and'longitudinal sectional view, on a large scale, of the apparatus disclosed in Fig. 1, with the parts disposed in theposi-tion for lowering the apparatus in a well bore, Fig. 2a constituting a lower continuation of Fig. 2 and Fig. 2b constituting a lower continuation of Fig. 2a;

Fig. 3 is a longitudinal section through the spring motor, disclosing the parts in the position they occupy following release of the spring motor;

' Fig. 4 is a view of the friction drag device and its control mechanism, with the parts in another operative positionf 7 Fig.5 is a view similar to Fig. 4, disclosing thefriction line 7-7 on Fig. 6. I

In the specific apparatus disclosed in the drawings, it is desired to generate an electric current for initiating operation of a fluid pressure operating device A, such as disclosed in United States Patent 2,618,343. The eleclt'riccurrent is supplied by a motongeneratordevice B secured to 'the upper end of the fluid pressure operating device, The motor portion of the motor generator de- \'tic e;'is"of'the spring type, being initially prevented from operating by 'a latch device C secured to the upper end ofithe motor generator device.

[The latch'ldevice C is releasable when 'a' friction drag device D'is' permitted; to 'engageit. Whether suchen-.

wall of the well casing disposed in the well bore, the

device effecting release of the spring motor'in response to upward movement of the running-in string.

Yet a further object of the invention is to provide a spring motor apparatus adapted to'be lowered in a well bore on a running-in string, and inwhich operation of the motor can be initiated by a friction drag device, manipulation of the running-in string causing the friction drag device to be secured in an ineifective position, if it is desired to avoid operation of the spring motor, once it has been lowered in the well bore.

Still another object of the invention is to provide apparatus to be lowered in a well bore on arunning-in string, and embodying a friction drag device for initiating operation of the apparatus in response to manipulation of the running-in string, in which the running-"in string can be manipluated to prevent the friction drag device from moving longitudinally of the running-in string and thereby forestall the friction drag device from v initiating operation of the apparatus;

secured to sinker bars F, the upper end of which'may be attached to a suitable running-in string G, such'as a wire line extending to the top of the well bore. Initially, the friction drag 'device D, which is slidable along the sinker'bars F, .dr'ag control device E and latch'device C is disposed in an upper positionon the sinker bars.

Only the upper portion of the fluid pressure operating device A, described in the above-identified patent, is shown in the drawings. Such device will generate a fluid pressure for the purpose of performing another operation in a well bore, such as to set a well packer (not shown) therewithin. The fluid pressure necessary for setting the well packer is derived through the combustion of a power charge 10 disposed in a cylinder 11 forming the upper part of the fluid pressure operating device. The initiation of the combustion of the power charge is secured by firing a cartridge 12 mountedin a gun barrel 13 threadedly attached to a cylinder head 14 that is threadedly secured to the upper end of the cylinder. Leakage of fluid between the gun barrel 13, on the one hand, andlthe cylinder Lland its head 14, on the other, hand, is prevented by suitableside seals 15, there also being a gasket 16 under the head of the 3 cartridge 12 to prevent leakage by the latter into and out of the cylinder.

The cartridge 12 has a suitable supplyof gunpowder therein, which is detonated in response to the passage of electric current through a filament (not shown) in the cartridge. In the present case, the electric current is supplied by an electric generator 17 of an'y suitable type, current from the generator passing through a suitable lead 18 to a series of suitable electric conducting elements '19, and to a spring pressed contact iztkthat engages a suitable contact point 21 at the upper end of the cartridge connected to one end of the cartridge filament. The other line from the generator is grounded, as

well as the connection running to the other end of the filament. The conductive elements 18, 19, running from the generator to the filament are surrounded by suitable insulators 22 to prevent short oircuiting of the 7 current from the generator, all in a known manner.

The cylinder head is threadedly secured to the lower end of a motor-generator casing 23, the upper end of which is threadedly attached onto the lower'end of a latch body'24 forming part of the latch device C for controlling the operation of the motor-generator set B. T

The generator 17 is clamped between an end plate 25 resting upon th'e'upper end of the cylinder head 14 and the upper flange portion 26 of a clamp sleeve 27 threadedly secured to the end plate. An armature shaft 28 extends upwardly from the generator casing, this shaft terminating in a non-circular socket 29 receiving a companion non-circular end 30 of a screw drive shaft 31 that extends upwardly in the housing 23 to a substantial extent.

The lower end 32 of the shaft 31 is rotatably mounted motor shaft 31, the lower end of the spline sleeve being threadedly attached tothe upper end of the clamp sleeve The drive shaft 31 forms the rotating part of a spring motor 39 which is adapted to rotate the armature shaft 28 at a rapid rate, which is'more than sufi icient to generate adequate current for heating the filamentin 'the cartridge 12 to the extent necessary for detonating the :7

latter, and causing ignition of the power charge 10 in the pressure cylinder 11. To secure rotation of the drive shaft 31 it is provided with a helical groove 40 of relatively steep pitch, the groove being located in an intermediate large diameter portion of the drive shaft,

beginning near the upper end of the large diameter portion and terminating at the lowermost end of the large diameter portion. In fact, the groove 40 actually runs out of the large diameter portion at its lower end, the

shaft portion 32 below such lower end being of a substantially reduced diameter and being rotatable in the lower bearing 33, as above described.

Cooperating with the shaft 31 is a nut device 41, which surrounds it. This nut device contains oppositely directed screws or keys 42 secured radially therewithin, the heads 43 of these keys being received within keyways or lengthwise slots 44 provided in the spline sleeve 38, these slots extending almost the complete length of the spline sleeve. Mounted on the inner end of one of the screws or keys 42 is a roller 44a extending into the helical groove 40 of the drive shaft. The roller diameter is substantially the same as the width of the groove 40, to minimize lost motion between the roller and the drive shaft 31. Preferably, the roller 44a .is mounted on .the radial screw 42 through the agency of anti-friction bearing elements 45.

The nut 41 is urged in a downward direction by a strong helical compression spring 46 encircling the drive shaft, the lower end of the spring bearing against the nut 41, and its upper end against the upper bearing support 37. The spring 46 is retained initially in its upper, highly compressed condition by a releasable latch mechanism 47 that is adapted to prevent rotation of the shaft 31. However, when the latch mechanism is released, the spring 46 is free to drivethe nut 41 downwardly very rapidly, the nut being prevented from rotating by the reception of its keys 42 in the keyways or slots 44in the spline sleeve 38. As a result of the reception ,of the, driving roller 44a in the helical drive shaft groove '40, the straight-line downward motion of the nut 41 causes rotation of the drive shaft 31, the spring shifting the nut downwardly to its fullest extent, as shown in Fig. 3, in which the roller 44:: rides out of the groove 40, thereby effecting a disconnection between the nut 41 and the drive shaft 31, the latter being free to continue rotating because of its own inertia. During the downward movement of the nut 41, the rotation of the drive shaftl31, of course, effects a corresponding rotation of the generator armature, such rotation continuing after the nut rides down oif the helical shaft, until all of the energy of the rotating parts has been absorbed. The electric current generated as a result of the above rotary motion is suflicient to heat the cartridge filament and detonate the cartridge 12.

The spring 46 is prevented from expanding initially through retention of the nut '41 in its uppermost position as a result of preventing rotation of the drive shaft 31.

The drive 'shaft has an upper threaded extension 50 integral therewith and threadedly receiving an upper brake member 51 having downwardly directed axial teeth 52 engageable with upwardly directed companion teeth 53 on a stationary brake member 54 surrounding a spacer sleeve 55 that engages an upwardly facing shoulder 5'6 on the drive shaft and the upper rotatable brake member 51. The stationary brake member 54 is prevented from rotating by a pair of radial screws 57 threaded into a release ring 58 freely encompassing the rotatable brake member 51',the heads 59 of the screws extending into longitudinal grooves, slots or keyways 60 in the upper portion of the upper bearing supporting member 37. The heads 59 of such screws also pass through holes 61 in the upwardly extending sleeve portion 62 of the stationary brake member 54. It is evident that the screws 57 effectively couple the stationary brake member 54 to .the upper bearing supporting member 37, which thereby prevents rotary movement of the stationary brake member 54. Y Y I The stationary 'brake member 54 is slidable longitudinally along the upper portion of the upper bearing support member 37. Such stationary brake member 54, as well as the release ring 58 coupled thereto through the agency of the screws 57, are urged in an upward direction, to maintain the stationary brake teeth 53 in engagement with the rotatable brake teeth 52, by a helical compression spring 63 bearing upon the lower end of the stationary brake member 54, and also upon a shoulder 64 provided in the bearing support 37. The spring 63 normally retains the brake teeth 52, 53 coengaged and prevents the drive shaft 31 from rotating, which will prevent the spring 46 from shifting the nut 41 downwardly along the drive shaft 31. p Y

The brake is releasable by a latch device carried within the latch body24, the lower end of which is secured to 'head and extending upwardly jinto the'b'ore 66' thereabove. -Leakage of fluid alongthe rod 70' is prevented by a suitable rod seal-ring 7Lclamped-against the head 65 by acup-shaped member 72' threaded onto the upper endfof the lowerhead.

' The upper end of the rod 70 is threadedly secured to the lower end of a release head;73 ,-which is urged in a downward direction by a helical compression spring 74 surrounding it, the lower end of the compression spring engaging a release head flange 75, and :its upper end engaging a shoulder 76 of the latch'body bore 66. The compression spring 74 tends to shift'the release head 73, rod 70 and brake release member 69 ina downward directionto release the brake, as hereinafter described.

However, it is'prevented from shifting downwardly by a pairvof diametrically opposed latches 77 located in a transverse slot 78in the latch body and pivotally mounted on fulcrum pins 79' extending across the slot. LThe latch members 77 have inwardly directed latch fingers 80 above their fulcrum pins adapted to ,fit-under a downwardly directed shoulder 81 of'therelea'se head '73, "the fingers being maintained in a latching position by-a tension spring 82 connected to and locatedbetweenthe upper ends of upwardly extending latch arm 83, from which the fingers 80 project inwardly. The lower parts of the latch members 77 are constituted ,as release legs 84 extending in a downward'and outward direction from the fulcrum pins 79, the ends 'of these :leg's projecting beyond the periphery of the latch body24 when the latch fingers 80 are disposed under theirrelease shoulder 81. The upper end 85 of the release head 73 is ta'per'ed to facilitate upward shifting of the release head pastlthe latch fingers 80 to the latched position disclosed in Fig.

2a. When the latch fingers are in the po-sitiondiscloscd" inFig. 2a, the release head 73, red 70 and cup-shaped release member 69 are held in their upward positions, the release member 69 being disposed just'a slightdistance above the release ring 58.": i i

exception, of the drag device .13, which will remain stationary, The entire apparatus is elevated until release legs 84 engage the lower downwardly diverting inner surface 92 on-the lower collar 88, which will force the release legs-inwardly-and thereby trip the releasehead 73,; which, in turn, willaffect disengagement of the positive tooth brake and permit the spring motor to operate. Accordingly, the spring motor is placed in operation as a resultof ,upwardrnanipulation of the running-in string G. a c I After the apparatus has been lowered in.the well casing, conditions may be encountered that warrant the removal of the apparatus from the well casing without operating the motor-generator vB. Since upward movelatch body 24. The upper end of the control-body is threadedly secured to the lower end of the string of sinker bars 'F'on which the drag; device D is originally disposedagainst,thezupper stop ring 91. The control body has an elongate longitudinal slot 94 therein conta'ining-a latch lever 95 having a central elongate slot 96 vreceivingqa fulcrum pin 97 secured to the control body- 93 and extending across its slot 94. "The latch When the release legs 84 are shifted inwardly, the V latch members swing about their fulcrums 79 to shift their fingers 80 and out of engagement with the release head shoulder 81. Accordingly, the helicalspring- 74 can expand and shift the release head 73, release rod '70 and release member 69'downwardly, 'thelatter 'engaging the release ring 58 and acting through the pins 57 to shift the -stationary brake member 54'downwardly against the force of the helical spring 63, freeing the stationary brake teeth-53 from the rotatable brake teeth 52; Releasing the restraint on the drive shaft31allows the spring 46 to shift the nut 41 downwardly to" its lowermost position disclosed in Fig. 3, during which time the shaft 31 is given a rapid rotation, by virtue of the radial movement of the nut roller 44a in the helical groove of the shaft. 7 a

To release the latches 77 by swinging their legs 84 inwardly in the manner just described, a-friction drag device D is provided that includes an upper collar 87 and a lower collar 88 spaced belowthe upper collar, there being outwardly disposed, circumferentially spaced drag springs 89 secured to both collars, as through use of l the upper and lower securing rings'90, which can, be

attached to the collars in any suitable manner, as by welding. As the apparatus is lowered-in a well casing (not shown) the outwardly bowed springs 89 frictionally drag along the wall of the'well casing, resisting downward movement of the drag device D.: 'However, a stop ring 91 is secured to one of the sinker bars F near the upper end of the latter, which engagesthe .uppercollar 87 and pushes the drag device D down the casing with the remainder of the apparatus, the drag springs 89frictionally sliding along the'wall of the casing.

When it is desired to trip thelatches 77 to elfect operation of the spring motor-generator set B, it is merely necessary to elevate the wire line G,- or other running-in string, to lift the entire apparatus in thewell casing, with lever is urged in a clockwise direction, as seen in Figs.

2a, 4zand 5, by a tension spring 9,8,--the lower end of Which-,is attachedto the latch lever. 95 to-the leftof the ,fulcrum pin 97, and. the upper end of which is attached to a suitableanchor pin 99 fixedto the control g body. The action of the spring 98 tendsjto shift the lower leg portion 100 of the latch lever to the left, which movementis limited byengagement of the lower'foot 101- of the latch with a stop pin 102 secured to the control body 93. The spring 98 also tends to elevate'the latch member 95 within the body 93 to the extent determined by engagement of the fulcrum pin 97 with the lower end of the slot 96-. Such'elevating movement also tends to hold a pair of spaced fingers 103, 104, proj'ecting upwardly from the arm 105 of the latch lever, on opposite sides of a holding pin 106 secured to the body 93 and extending across its slot 94.

Initially, the parts of the drag control device E occupy the position disclosed in Fig. 2a, in which the spring 98 holds the arm 105 of the latch lever 95 inwardly of the control body 93, with its spaced fingers 103, 104 disposed on opposite sides of the holding pin 106. The hold-ingpin'engages the left finger 103 and prevents the spring 98 from shifting the latch leg 100 inwardly of the slot 94 into engagement .with its stop pin 102; Instead, when the holding pin 106 is engaging theleft finger 103 of the latch, its feet portion 101 extends out of theslot 94 to a certain extent, as clearly disclosed in Fig. 2a.

When the drag control'd'evice E is conditioned as shown in Fig. 2a, the friction drag spring device D is ning-instring Gis elevated, which will elevate the sinker oars F'and all of the mechanism therebelow, thedrag device D being held stationary by frictional engagement of its leaf springs 89 against the wall of the well casing.

As the controldevice E is pulledupwardly through the drag d'eviceD, the lower collar 88 of the dragjdevice will engage the outwardly projecting foot portion .101 of V I thelatchmember and ,shiftthe latchdownwardly against the force of the tension spring 98 (as illustrated in Fig. 4), until the latch device slides down along the fulcrum pin 97 and the holding pin 106 to the extent at Whichthe left finger 103 is disposed below the holding pin. When this occurs, the spring 98 is effective to turn the latch lever 95 in a clockwise direction sufiiciently to bring the foot portion 101 inwardly and to shift the arm portion 105 and fingers 103, 104 in an outward direction, the inner finger 103 then being disposed under the holding pin 106, which will prevent the latch lever 95 from moving back to its initial position shown in Fig. 2a. At the time the left finger 103 can release from the holding pin 106, the upper collar 87 is already sliding relatively down. along the control body slot 94 and is disposed opposite the right finger 104, which Will prevent any outward movement of the arm 105 with respect to the slot 94. The running-in string G, and all the other mechanism attached thereto, with the exception of the drag device D, can continue to move upwardly until the lower collar 88 of the drag device engages the latch legs 84 and releases the latches 77 from the release head 73, allowing the brake to be released from the drive shaft 31, in the mannerdescribed above. The drive shaft will rotate the generator 17, the latter feeding current to the cartridge 12, firing the latter and causing the power charge 10 to function and operate or anchor the bridge plug or other mechanism described in the above-identified patent in the well casing, after which the fluid pressure operated device A is automatically released from the bridge plug. The entire apparatus disclosed can now be elevated in the well casing and withdrawn to the top of the well bore.

If, however, it is not desired to operate the spring motor, the friction drag device D can be rendered ineffective. With the parts in their initial position, such as disclosed in Figs; 1, 2, 2a and 2b, the running-in string G is elevated to pull all the apparatus upwardly with respect to the drag device D. However, elevation only occurs to the extent at which the drag device D engages the latch lever foot 101 and shifts the latch lever 95 downwardly to release its right finger 103 from the" holding pin 106. In any event, the drag device D is not permitted to move relatively down along the apparatusto the extent sufficient to engage the release legs 84. After the left finger 103 has been released from the holding pin 106, the apparatus is again lowered in the well casing, the friction drag device being prevented from lowering by its frictional engagement against the wall of the well casing. In other words, the friction drag device'D will shift upwardly along the control body 93, and when its upper collar 87 moves above the right finger 104, the spring 98 is effective to rock the latch lever 95 in a clockwise directionand engage the foot 101 with the stop pin 102, which will locate the right finger 104 outwardly of the control body 93. The running-in string G and all of the apparatus, with the exception of the drag device D, are now elevated. The latch lever arm 105 will then engage the lower end of the upper collar 87 ofthe drag device, which is disposed betwe'en the fingers 103, 104, the lever 95 being shifted downwardly until the upper end of the slot 96 engages the fulcrum pin 97. When such engagement occurs, further downward movementof the latch lever 95 along the control body 93 cannot occur, so that elevation of the running-in string G will act through the latch lever 95 to elevate the drag device D in the well bore along with all of the other mechanisms secured to the running-in string. The entire apparatus can be elevated in the well casing and removed to the top of the hole, the drag device D being prevented from moving relatively downwardly along the control device E into engagement with the latch device C to shift the latch legs'84 inwardly and release the brake mechanism.

It is, accordingly, apparent that an apparatus has been provided in whichla simple and exceedingly powerful and sturdy spring motor is provided for rapidly rotating the generator to supply sufiicient current for operating another device in a well bore, such'as to fire the cartridge along said shaft.

12. The spring motor is prevented from operating until desired. When its operation is to occur, it is merely necessary to elevate the running-in string G a predetermined amount, which will cause the friction drag device D to effect a release of the spring motor brake or latch mechanism. If, however, the spring motor is not to be operated and the apparatus withdrawn from the well bore, the friction drag device D can be rendered ineffective merely through appropriate manipulation of the running-in string.

The inventors claim:

1. In well apparatus adapted to be disposed in a well bore: a device to be operated in the well bore; a generator disposable in the well bore with its axis longitudinally of the well bore and electrically connected to said device for supplying current to said device; a spring motor, said motor including a drive shaft member substantially coaxial of said generator connected to said generator to rotate the same and a nut member surrounding said drive shaft member, means mounting said nut member for longitudinal slidable movement and against substantial rotation with said shaft member, one of said members having a helical thread thereon and the other of said members having means thereon engaging said thread, a spring for shifting said nut along said shaft to rotate said shaft, means connected to said spring for retaining said spring in a stressed condition and for preventing operation of said spring, said retaining means including releasable brake means, and means for releasing said brake means to permit said spring to shift said nut along said shaft.

2. In well apparatus adapted to be disposed in a well bore: a device to be operated in the well bore; a generator disposable in the well bore with its axis longitudinally of the well bore and electrically connected to said device for supplying current to said device; a spring motor, said motor including a drive shaft substantially coaxial of said generator connected to said generator to rotate the same and having a helical thread thereon and a nut surrounding said shaft and engaging said thread, means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft, a spring for propelling said nut along said shaft to rotate said shaft, said thread permitting said nut to be disengaged from said shaft, means connected to said spring for retaining said spring in a stressed condition and for pre venting operation of said spring, said retaining means including releasable brake means, and means for releasing said brake means to permit said spring to shiftsaid nut 3. In Well apparatus adapted to'be disposed in a well bore: a device to be operated in the well bore; a generator disposable in the well bore with its axis longitudinally of the well bore and electrically connected to said device for supplying current to said device; a spring motor, said motor including a drive shaft substantially coaxial of said generator connected to said generator to rotate the same and having a helical thread thereon and a nut surrounding said shaft and engaging said thread, means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft, a spring for propelling said nut along said shaft to rotate said shaft, said threadsv permitting said nut to be disengaged from said shaft, means connected to said spring for retaining said spring in a stressed condition and for preventing operation of said spring, said retaining means including releasable brake means, and means for releasing said brake means to permit said spring to shift said nut along said shaft.

4. In well apparatus adapted to be disposed in a well bore on a running-in string: a device to be operated in the 7 well bore a generator disposable in the well bore and elecshaft member connected to said generator to rotate the sameand a nut member surroundingsaid drive shaft member, means mounting said ,nut member forlongitudinal slidable movement and "against substantial rotation with said shaft member, one of said members having a helical thread thereon and the other ofsaid members .having means thereon engaging saidthread, a spring for shifting said nut along said shaft to rotate said shaft, means. connected to said spring for retaining said spring in a stressed c'onditionandfor preventing operation of said spring, said retaining means including releasable brake means; andv means responsive to manipulation of saidrunning-in string for releasing said brfake means to permit said spring to shift said nut alongsaid shaft, U j

the well-bore; a generator disposable in the well bore and electrically connected to, said device for supplying current to said device; a spring motor, said motorincluding a drive shaft member connected to said generator to rotate the same and a nut member surrounding said drive shaft member, means mountingsaid; nut member for longitudinal slidable movement and against substantial rotation with'said shaft-member, one of said members having a helical thread thereon and the other of said members having means thereon engaging said thread, a spring for shifting said nut along-said shaft torotate said shaft,v means connected to; said spring for retaining said spring in a stressedcondition and for preventingoperation, of said spring, said retaining means'includingre- 1 leasable brake means; means responsive to manipulation of said running-in string for releasing said brake means to permit .said spring to shiftrsaid nut along'l said shaft; and means responsive to' manipulation of said running in string for preventing operation of said releasing means.

6. In well apparatus 'adaptedto be disposed in a well bore: a device. to be operated in the well here; a generator disposable in the well bore-and electrically connected to said device for supplying current torsaid device; a spring motor, said. motor including a drive shaft having a helical thread thereon and connectedto said generator to rotate the same and a nut surrounding said shaftand disengaged from said shaft; releasable brake means engaging said shaft to prevent its rotation with said nut disposedin an upper position onsaid shaft and said spring "in'a compressed condition; and means for releasing said brake means.

' 5. In well apparatus adapted to be disposed in a well here on a running-in string: a device to be operated in T0 bore of; 'a riiiining-instringz a device to be operated in the wellbore; a generator disposable in the well bore'and electrically connected to said device for supplying current to said device; a spring motor, said motor including a drive shaft'having a helical thread thereon and connected to said generator to rotate the same and a nut surrounding said shaft and engaging said thread, means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft, a compressed helical spring above said nu-tfor shifting said; nut'downwardly along said shaft to rotate said shaft, said threadpermitting said nutto be disengaged from said shaft; releasab'le brake means engaging said shaft to pr event its rotation with said nut disposed in an upper positionon said shaft and said spring a compressed condition;

means for releasing said brake means, comprising a friction drag device frictionally engageable with the wall of a well casing containing the apparatus, said releasing means being operable to release said brake means in response to upward movement of the runningqin string in the wellc-asing; and means responsive to manipulation of the well bore; a generator disposable in the well bore and electrically connected to said device for supplying current to said device; a spring'motor, said motor including a I drive shaft having a helical'thread thereon and connected tofsaid generator to rotate the same and a nut surrounding said shaft and engaging said thread, means mounting said nut for longitudinal slidable movement' and against substantial rotation with said shaft, a compressed helical spring above said nut for shifting said nut downwardly along s'aid shaft to rotate said shaft, said thread per- :mitti'ng' said nu't to be disengaged from said shaft; :1 releasablebralge means "engaging said shaft to prevent its "rotation with said nut disposed in an upper position on said; shaft and said spring in a compressed condition; means for releasing said brake means, comprising a friction'drag'device frictionally engageable with the wall of a well 'casing containing the apparatus, said releasing means being operable to release said brake means in response to upward movement of the running-in stringin the welteasing'; and a latch device located initially below 7; In well apparatus adapted tov be disposed a' wellv bore on a running-in string: a deviceto be operatedin the wellbore; a generator disposable in the well bore and electrically connected tosaid device for supplying current to said device; a springmotor, said motor including a drive shaft having a helical thread thereon and connected to'said generator to rotate the same and a nut surrounding said shaft and engaging said thread, means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft, a compressed helical spring above said nut for shifting said nut downwardly along said'shaft to rotate said shaft, said thread permitting said nut to be disengaged from said shaft; re-

leasable brake means engaging said shaft to prevent its rotation with said nut disposed in an upper position on said shaft and said spring in a compressed condition; and v means for releasing said brake means, comprising a fric-- i tion drag device frictionally engageable with the wall of V the well casing. t

S. In well apparatus adapted to be disposed in 'a well said friction drag device with a portion of said latch device in an inward ineffective position allowing relative downward movement of said friction drag device therealong "toa brake means releasing position; said friction drag" device engaging said latch device when moving downwardly therealon'g'to place said portion of said latch device in an outward effective position for coupling to said friction drag device in the event said friction drag device is moved'upward relatively along said latch device andthen relatively downward therealong.

10. In well apparatus adapted to be disposed in well lbo re: a device to be operated in the well bore; a gen- "erator disposable in the well bore and electrically con- 'nected to said device for supplying current to said device; a spring motor, said motor including a drive shaft having a helical thread thereon and connected to said generator to rotate the same and a nut surrounding said shaft and engaging said thread, means mountingsaid nut for longitudinal slidable movement and against substantial rotation with said shaft, a compressed helical spring above disposedin an upper position onsaid shaft andsaid I spring in a compressed condition; means movable downwardly torelease said brake means; releasable latch means-initially preventing downward movement of said brake releasing means; and friction drag means movable in a downward direction with respect to said latch means to release said latch means.

11. In well apparatus adapted to be disposed in a well bore: a device to be operated in the well bore; a generator disposable in the well bore and electrically connected to said device for supplying current to said device; a spring motor, said motor including a drive shaft having a helical thread thereon and connected to said generator to rotate the same and a nut surrounding said shaft and engaging said thread, means mounting said nut for longi tudinal slidable movement and against substantial rotation with said shaft, a compressed helical spring above said nut for shifting said nut downwardly along said shaft to rotate said shaft, said thread permitting said nut to be disengaged from said shaft; releasable brake means engaging said shaft to prevent its rotation with said nut disposed in an upper position on said shaft and said spring in a compressed condition; means movable downwardly to release said brake means; releasable latch means initially preventing downward movement of said brake releasing means; friction drag means movable in a downward direction with respect to said latch means to release said latch means; a latch device above said latch means and located initially below said friction drag device with a portion of said latch device in an inward inefiective posi-. tion allowing relative downward movement of said friction drag device into engagement with said latch means; said friction drag device engaging said latch device when moving downwardly therealong to place said portion of said latch device in an outward effective position for coupling to said friction drag device in the event said friction drag'device is moved upward relatively along said latch device and then relatively downward therealong.

12. In well apparatus to be disposed in a well bore on a running-in string: a drive shaft having a helical thread thereon and a nut surrounding said shaft and engaging said thread; means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft; a spring for propelling said nut along said shaft to rotate said shaft, said thread permitting said nut to be disengaged from said shaft to permit said shaft to continue rotating; means connected to said spring for retaining said spring in a stressed condition and for preventing operation of said spring, said retaining means including releasable brake means, and means for releasing said brake means to permit said spring to shift said nut along said shaft.

13. In well apparatus adapted to be disposed in a well bore on a running-in string: a drive shaft having a helical thread thereon and a nut surrounding said shaft and engaging said thread; means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft; aspring for propelling said nut along said shaft to rotate said shaft, said thread permitti-ng'said nut to be disengaged from said shaft to permit said shaft to continue rotating in a stressed condition.

14. In well apparatus adapted to be disposed in a well bore on a running-in string: a drive shaft having a helical thread thereon and a nut surrounding said shaft and engaging said thread; means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft; a compressed helical spring above said not for shifting said nut downward along said shaft to rotate said shaft, said thread permitting said nut to be disengaged from said shaft to permit said shaft to continue rotating; releasable brake means engaging said shaft to prevent its rotation with said nut disposed in an upper position on said shaft and said spring in a compressed condition; and means for releasing said brake means.

15. In well apparatus adapted to be disposed in a well bore on a running-in string: a drive shaft having a helical thread thereon and a nut surrounding said shaft and engaging said thread; means mounting said nut for longitudinal slidable movement and against substantial rota- 12 tion with said shaft; a compressed helical spring above said nut for shifting said nut downward along said shaft to rotate said shaft, said thread permitting said nut to be disengaged from said shaft; releasable brake means engaging said shaft to prevent its notation with said nut disposed in an upper position on said shaft and said spring in a compressed condition; means for releasing said brake means comprising a friction drag device frictionally engageable with the wall of a well casing containing the apparatus, said releasing means being operable to release said brake means in response to upward movement of the runningin string in the well casing; and means responsive to manipulation of said running-in string for preventing movement of said releasing means and its friction drag device to a brake means releasing position.

16. in well apparatus adapted to be disposed in a well bore on a running-in string: a drive shaft having a helical thread thereon and a nut surrounding said shaft and engaging said thread; means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft; a compressed helical spring above said nut for shifting said nut downwardly along said shaft to rotate said shaft, said thread permitting said nut to be disengaged from said shaft; releasable brake means engaging said shaft to prevent its rotation with said nut disposed in an upper position on said shaft and said spring in a compressed condition; means movable downwardly to release said brake means; releasable latch means initially prevent downward movement of said brake releasing means; and friction drag means movable in a downward direction with respect to said latch means to release said latch means.

17. In well apparatus adapted to be disposed in a well bore on a running-in string: a drive shaft having a helical thread thereon and a nut surrounding said shaft and engaging said thread; means mounting said nut for longitudinal slidable movement and against substantial rotation with said shaft; a compressed helical. spring above said nut for shifting said nut downwardly along said shaft to rotate said shaft, said thread permitting said nut to be disengaged from said shaft; releasable brake means engaging said shaft to prevent its rotation with said nut disposed in an upper position on said shaft andsaid spring in a compressed condition; means movable downwardly to release said brake means; releasable latch means initially preventing downward movement of said brake releasing means; friction drag means movable in a downward direction with respect to said latch means to release said latch means; a latch device above said latch means located initially below said friction drag device with a portion of said latch device in an inward ineffective position allowing relative downward movement of said friction drag device into engagement with said latch means; said friction drag device engaging said latch device when moving downwardly therealong to place said portion of said latch device in an outward effective position for coupling to said friction drag device in the event said friction drag device is moved upward relatively along said latch device and then relatively downward therealong.

18. In well apparatus adapted to be disposed in a well bore on a running-in string: supporting means connectible to the running-in string; a friction drag device movable longitudinally with respect to said supporting means; a latch device on said supporting means located initially below said friction drag device with a portion of said latch device in an inward inefiective position allowing relative downward movement of said friction drag device therealong; means on said friction drag device engaging said latch device when said friction drag device moves in said relative downward directionto place said portion of said latch device in an outward effective position for coupling to said friction drag device in the event said friction drag device is moved upwardly along said latch device and then relatively downward therealong.

19. In well apparatus adapted to be disposed in a well bore on a running-in string: supporting means connectible to the running-in string; a friction drag device movable longitudinally with respect to said supporting means; a latch lever on said supporting means located initially below saidfriction drag device; means on said supporting means engaging said lever to hold a coupling portion of said lever in an inward position on said supporting means to allow relative downward movement of said friction drag device along said lever; means on said lever engaged by said friction drag device when said friction drag device moves in said relative downward direction to release said lever from said holding means and allow said coupling pontion to project outwardly of said supporting means; said outwardly projecting coupling portion be- 15 ,764, 7

coming coupled to said friction drag device in the event said friction drag device is moved relatively upward along said lever and then relatively downward therealong.

7 References Cited in the file of this patent UNITED STATES PATENTS 867,063 Lillie Sept. 24, 1907 2,202,887 Aloi June 4, 1940 2,315,775 DArcey Apr. 6, 1943 2,389,711 Armentrout Nov. 27, 1945 2,618,343 Conrad Nov. 18, 1952 2,630,067 McWhor ter Mar. 3, 1953 2,637,402 Baker et a1. May 5, 1953 Otto Sept. 25, 1956 

